The present invention relates to apparatus for obtaining information about an occupying item of a seat, in particular, a seat in an automotive vehicle.
The present invention also relates to apparatus and methods for adjusting a vehicle component, system or subsystem in which the occupancy of a seat, also referred to as the xe2x80x9cseated statexe2x80x9d herein, is evaluated using at least a weight measuring apparatus and the component, system or subsystem may then be adjusted based on the evaluated occupancy thereof. The vehicle component, system or subsystem, hereinafter referred to simply as a component, may be any adjustable component of the vehicle including, but not limited to, the bottom portion and backrest of the seat, the rear view and side mirrors, the brake, clutch and accelerator pedals, the steering wheel, the steering column, a seat armrest, a cup holder, the mounting unit for a cellular telephone or another communications or computing device and the visors. Further, the component may be a system such an as airbag system, the deployment or suppression of which is controlled based on the seated-state of the seat. The component may also be an adjustable portion of a system the operation of which might be advantageously adjusted based on the seated-state of the seat, such as a device for regulating the inflation or deflation of an airbag that is associated with an airbag system.
The present invention also relates to apparatus and method for automatically adjusting a vehicle component to a selected or optimum position for an occupant of a seat based on at least two measured morphological characteristics of the occupant, one of which is the weight of the occupant. Other morphological characteristics include the height of the occupant, the length of the occupant""s arms, the length of the occupant""s legs, the occupant""s head diameter, facial features and the inclination of the occupant""s back relative to the seat bottom. Other morphological characteristics are also envisioned for use in the invention including iris pattern properties from an iris scan, voice print and finger and hand prints.
Automobiles equipped with airbags are well known in the prior art. In such airbag systems, the car crash is sensed and the airbags rapidly inflated thereby insuring the safety of an occupation in a car crash. Many lives have now been saved by such airbag systems. However, depending on the seated state of an occupant, there are cases where his or her life cannot be saved even by present airbag systems. For example, when a passenger is seated on the front passenger seat in a position other than a forward facing, normal state, e.g., when the passenger is out of position and near the deployment door of the airbag, there will be cases when the occupant will be seriously injured or even killed by the deployment of the airbag.
Also, sometimes a child seat is placed on the passenger seat in a rear facing position and there are cases where a child sitting in such a seat has been seriously injured or killed by the deployment of the airbag.
Furthermore, in the case of a vacant seat, there is no need to deploy an airbag, and in such a case, deploying the airbag is undesirable due to a high replacement cost and possible release of toxic gases into the passenger compartment. Nevertheless, most airbag systems will deploy the airbag in a vehicle crash even if the seat is unoccupied.
For these reasons, there has been proposed a seated-state detecting unit such as disclosed in the following U.S. patents, which are incorporated herein by reference in their entirety to the extent the disclosure of these patents is necessary, assigned to the current assignee of the present application: Breed et al. (U.S. Pat. No. 5,563,462); Breed et al. (U.S. Pat. No. 5,829,782); Breed et al. (U.S. Pat. No. 5,822,707); Breed et al. (U.S. Pat. No. 5,694,320); Breed et al. (U.S. Pat. No. 5,748,473); and Varga et al. (U.S. Pat. No. 5,943,295); Breed et al. (U.S. Pat. No. 6,078,854); and Breed et al. (U.S. Pat. No. 6,134,492). Typically, in some of these designs as many as three or four sensors or sets of sensors are installed at three or four points in a vehicle passenger compartment for transmitting ultrasonic or electromagnetic waves toward the passenger or driver""s seat and receiving the reflected waves. Using appropriate hardware and software, the approximate configuration of the occupancy of either the passenger or driver seat can be determined thereby identifying and categorizing the occupancy of the relevant seat.
However, in the aforementioned literature using ultrasonics, the pattern of reflected ultrasonic waves from an adult occupant who may be out of position is sometimes similar to the pattern of reflected waves from a rear facing child seat. Also, it is sometimes difficult to discriminate the wave pattern of a normally seated child with the seat in a rear facing position from an empty seat with the seat in a more forward position. In other cases, the reflected wave pattern from a thin slouching adult with raised knees can be similar to that from a rear facing child seat. In still other cases, the reflected pattern from a passenger seat which is in a forward position can be similar to the reflected wave pattern from a seat containing a forward facing child seat or a child sitting on the passenger seat. In each of these cases, the prior art ultrasonic systems can suppress the deployment of an airbag when deployment is desired or, alternately, can enable deployment when deployment is not desired. Similar confusing situations can occur also for capacitive, electric field and optical occupant sensing systems.
If the discrimination between these cases can be improved, then the reliability of the seated-state detecting unit can be improved and more people saved from death or serious injury. In addition, the unnecessary deployment of an airbag can be prevented.
With respect to the adjustment of a vehicular seat, the adjustment of an automobile seat occupied by a driver of the vehicle is now accomplished by the use of either electrical switches and motors or by mechanical levers. As a result, the driver""s seat is rarely placed at the proper driving position which is defined as the seat location which places the eyes of the driver in the so-called xe2x80x9ceye ellipsexe2x80x9d and permits him or her to comfortably reach the pedals and steering wheel. The xe2x80x9ceye ellipsexe2x80x9d is the optimum eye position relative to the windshield and rear view mirror of the vehicle.
The eye ellipse, which is actually an ellipsoid, is rarely achieved by the actions of the driver for a variety of reasons. One specific reason is the poor design of most seat adjustment systems particularly the so-called xe2x80x9c4-way-seatxe2x80x9d. It is known that there are three degrees of freedom of a seat bottom, namely vertical, longitudinal, and rotation about the lateral or pitch axis. The 4-way-seat provides four motions to control the seat: (1) raising or lowering the front of the seat, (2) raising or lowering the back of the seat, (3) raising or lowering the entire seat, (4) moving the seat fore and aft. Such a seat adjustment system causes confusion since there are four control motions for three degrees of freedom. As a result, vehicle occupants are easily frustrated by such events as when the control to raise the seat is exercised, the seat not only is raised but is also rotated. Occupants thus find it difficult to place the seat in the optimum location using this system and frequently give up trying leaving the seat in an improper driving position
Many vehicles today are equipped with a lumbar support system that is never used by most occupants. One reason is that the lumbar support cannot be preset since the shape of the lumbar for different occupants differs significantly, i.e., a tall person has significantly different lumbar support requirements than a short person. Without knowledge of the size of the occupant, the lumbar support cannot be automatically adjusted.
As discussed in the above referenced ""320 patent, in approximately 95% of the cases where an occupant suffers a whiplash injury, the headrest is not properly located to protect him or her in a rear impact collision. Also, the stiffness and damping characteristics of a seat are fixed and no attempt is made in any production vehicle to adjust the stiffness and damping of the seat in relation to either the size or weight of an occupant, or to the environmental conditions such as road roughness. All of these adjustments, if they are to be done automatically, require knowledge of the morphology of the seat occupant.
Systems are now being used to attempt to identify the vehicle occupant based on a coded key or other object carried by the occupant. This requires special sensors within the vehicle to recognize the coded object. Also, the system only works if the coded object is used by the particular person for whom the vehicle was programmed. If the vehicle is used by a son or daughter, for example, who use their mother""s key then the wrong seat adjustments are made. Also, these systems preserve the choice of seat position without any regard for the correctness of the seat position. With the problems associated with the 4-way seats, it is unlikely that the occupant ever properly adjusts the seat. Therefore, the error will be repeated every time the occupant uses the vehicle.
Moreover, these coded systems are a crude attempt to identify the occupant. An improvement can be made if the morphological characteristics of the occupant can be measured as described below. Such measurements can be made of the height and weight, for example, and used not only to adjust a vehicular component to a proper position but also to remember that position, as fine tuned by the occupant, for re-positioning the component the next time the occupant occupies the seat. For the purposes herein, a morphological characteristic will mean any measurable property of a human such as height, weight, leg or arm length, head diameter, facial features, iris patterns, voice, finger or hand prints etc.
As discussed more fully below, in a preferred implementation, once at least one and preferably two of the morphological characteristics of a driver are determined, e.g., by measuring his or her height and weight, the component such as the seat can be adjusted and other features or components can be incorporated into the system including, for example, the automatic adjustment of the rear view and/or side mirrors based on seat position and occupant height. In addition, a determination of an out-of-position occupant can be made and based thereon, airbag deployment suppressed if the occupant is more likely to be injured by the airbag than by the accident without the protection of the airbag. Furthermore, the characteristics of the airbag including the amount of gas produced by the inflator and the size of the airbag exit orifices can be adjusted to provide better protection for small lightweight occupants as well as large, heavy people. Even the direction of the airbag deployment can, in some cases, be controlled.
Still other features or components can now be adjusted based on the measured occupant morphology as well as the fact that the occupant can now be identified. Some of these features or components include the adjustment of seat armrest, cup holder, steering wheel (angle and telescoping), pedals, visors phone location and for that matter the adjustment of all things in the vehicle which a person must reach or interact with. Some items that depend on personal preferences can also be automatically adjusted including the radio station, temperature, ride and others.
xe2x80x9cPattern recognitionxe2x80x9d as used herein will generally mean any system which processes a signal that is generated by an object (e.g, representative of a pattern of returned or received impulses, waves or other physical property specific to and/or characteristic of and/or representative of that object) or is modified by interacting with an object, in order to determine to which one of a set of classes that the object belongs. Such a system might determine only that the object is or is not a member of one specified class, or it might attempt to assign the object to one of a larger set of specified classes, or find that it is not a member of any of the classes in the set. The signals processed are generally a series of electrical signals coming from transducers that are sensitive to acoustic (ultrasonic) or electromagnetic radiation (e.g., visible light, infrared radiation, radar, or any other frequency), although other sources of information are frequently included.
A trainable or a trained pattern recognition system as used herein generally means a pattern recognition system which is taught to recognize various patterns constituted within the signals by subjecting the system to a variety of examples. The most successful such system is the neural network or modular neural network. Thus, to generate the pattern recognition algorithm, test data is first obtained which constitutes a plurality of sets of returned waves, or wave patterns or other data, from an object (or from the space in which the object will be situated in the passenger compartment, i.e., the space above the seat) and an indication of the identity of that object, (e.g., a number of different objects are tested to obtain the unique wave patterns from each object). As such, the algorithm is generated, and stored in a computer processor, and which can later be applied to provide the identity of an object based on the wave or other pattern being received during use by a receiver connected to the processor and other information. For the purposes here, the identity of an object sometimes applies to not only the object itself but also to its location and/or orientation in the passenger compartment. For example, a rear facing child seat is a different object than a forward facing child seat and an out-of-position adult is a different object than a normally seated adult.
Other means of pattern recognition exist where the training is done by the researcher including Fuzzy Logic and Sensor Fusion systems.
To xe2x80x9cidentifyxe2x80x9d as used herein will generally mean to determine that the object belongs to a particular set or class. The class may be one containing, for example, all rear facing child seats, one containing all human occupants, or all human occupants not sitting in a rear facing child seat depending on the purpose of the system. In the case where a particular person is to be recognized, the set or class will contain only a single element, i.e., the person to be recognized.
To xe2x80x9cascertain the identity ofxe2x80x9d as used herein with reference to an object will generally mean to determine the type or nature of the object (obtain information as to what the object is), i.e., that the object is an adult, an occupied rear facing child seat, an occupied front facing child seat, an unoccupied rear facing child seat, an unoccupied front facing child seat, a child, a dog, a bag of groceries, etc.
An xe2x80x9cobjectxe2x80x9d or xe2x80x9coccupying itemxe2x80x9d of a seat may be a living occupant such as a human or a dog, another living organism such as a plant, or an inanimate object such as a box or bag of groceries or an empty child seat.
xe2x80x9cOut-of-positionxe2x80x9d as used for an occupant will generally mean that the occupant, either the driver or a passenger, is sufficiently close to the occupant protection apparatus (airbag) prior to deployment that he or she is likely to be more seriously injured by the deployment event itself than by the accident. It may also mean that the occupant is not positioned appropriately in order to attain the beneficial, restraining effects of the deployment of the airbag. As for the occupant being too close to the airbag, this typically occurs when the occupant""s head or chest is closer than some distance such as about 5 inches from the deployment door of the airbag module. The actual distance value where airbag deployment should be suppressed depends on the design of the airbag module and is typically farther for the passenger airbag than for the driver airbag.
xe2x80x9cTransducerxe2x80x9d as used herein will generally mean the combination of a transmitter and a receiver. In some cases, the same device will serve both as the transmitter and receiver while in others two separate devices adjacent to each other will be used. In some cases, a transmitter is not used and in such cases transducer will mean only a receiver. Transducers include, for example, capacitive, inductive, ultrasonic, electromagnetic (antenna, CCD, CMOS arrays), weight measuring or sensing devices.
xe2x80x9cAdaptationxe2x80x9d as used here represents the method by which a particular occupant sensing system is designed and arranged for a particular vehicle model. It includes such things as the process by which the number, kind and location of various transducers is determined. For pattern recognition systems, it includes the process by which the pattern recognition system is taught to recognize the desired patterns. In this connection, it will usually include (1) the method of training, (2) the makeup of the databases used for training, testing and validating the particular system, or, in the case of a neural network, the particular network architecture chosen, (3) the process by which environmental influences are incorporated into the system, and (4) any process for determining the pre-processing of the data or the post processing of the results of the pattern recognition system. The above list is illustrative and not exhaustive. Basically, adaptation includes all of the steps that are undertaken to adapt transducers and other sources of information to a particular vehicle to create the system that accurately identifies and determines the location of an occupant or other object in a vehicle.
Heretofore, various methods have been proposed for measuring the weight of an occupying item of a vehicular seat. The methods include pads, sheets or films that have placed in the seat cushion which attempt to measure the pressure distribution of the occupying item. Prior to its first disclosure in U.S. Pat. No. 5,822,707 referenced above, systems for measuring occupant weight based on the strain in the seat structure as disclosed therein had not been considered. Prior art weight measurement systems have been notoriously inaccurate. Thus, a more accurate weight measuring system is desirable. The strain and bladder weight measurement systems described herein, substantially eliminate the inaccuracy problems of prior art systems and permit an accurate determination of the weight of the occupying item of the vehicle seat. Additionally, as disclosed herein, in many cases, sufficient information can be obtained for the control of a vehicle component without the necessity of determining the entire weight of the occupant. For example, the force that the occupant exerts on one of the three support members may be sufficient.
A xe2x80x9cvehiclexe2x80x9d as used herein will generally mean a self-propelled land vehicle such as a car, truck or bus, but can also encompass airplanes, trains (locomotives and non-self-propelled cars), boats and non-self-propelled and vehicles such as truck trailers.
Most, if not all, of the problems discussed above are difficult to solve or unsolvable using conventional technology.
Accordingly, it is a principal object of the present invention to provide new and improved apparatus for obtaining information about an occupying item on a vehicle seat which apparatus may be integrated into vehicular component adjustment apparatus and methods which evaluate the occupancy of the seat and adjust the location and/or orientation relative to the occupant and/or operation of a part of the component or the component in its entirety based on the evaluated occupancy of the seat.
Additional objects and advantages of this invention or other disclosed inventions include:
1. to provide new and improved vehicular seats in which the weight applied by an occupying item to the seat is measured based on capacitance between conductive and/or metallic members underlying the seat cushion.
2. to provide new and improved adjustment apparatus and methods that evaluate the occupancy of the seat and adjust the location and/or orientation relative to the occupant and/or operation of a part of the component or the component in its entirety based on the evaluated occupancy of the seat and on a measurement of the occupant""s weight or a measurement of a force exerted by the occupant on the seat.
3. to provide new and improved adjustment apparatus and methods that evaluate the occupancy of the seat by a combination of ultrasonic sensors and additional sensors and adjust the location and/or orientation relative to the occupant and/or operation of a part of the component or the component in its entirety based on the evaluated occupancy of the seat.
4. to provide new and improved adjustment apparatus and methods that reliably discriminate between a normally seated passenger and a forward facing child seat, between an abnormally seated passenger and a rear facing child seat, and whether or not the seat is empty and adjust the location and/or orientation relative to the occupant and/or operation of a part of the component or the component in its entirety based thereon.
5. to provide an improved weight measurement system and thereby improve the accuracy of another apparatus or system which utilizes measured weight as input, e.g., a component adjustment apparatus.
6. to provide new and improved adjustment apparatus and methods that evaluate the occupancy of the seat without the problems mentioned above.
7. to provide a system for passively and automatically adjusting the position of a vehicle component to a near optimum location based on the size of an occupant.
8. to provide a system for recognizing a particular occupant of a vehicle and thereafter adjusting various components of the vehicle in accordance with the preferences of the recognized occupant.
9. to provide systems for approximately locating the eyes of a vehicle driver to thereby permit the placement of the driver""s eyes at a particular location in the vehicle.
10. to provide a pattern recognition system to permit more accurate location of an occupant""s head and the parts thereof and to use this information to adjust a vehicle component.
11. to provide a method of determining whether a seat is occupied and, if not, leaving the seat at a neutral position.
12. to provide a system for automatically adjusting the position of various components of the vehicle to permit safer and more effective operation of the vehicle including the location of the pedals and steering wheel.
13. to determine whether an occupant is out-of-position relative to the airbag and if so, to suppress deployment of the airbag in a situation in which the airbag would otherwise be deployed.
14. to adjust the flow of gas into and/or out of the airbag based on the morphology and position of the occupant to improve the performance of the airbag in reducing occupant injury.
15. to provide a system where the morphological characteristics of an occupant are measured by sensors located within the seat.
16. to provide a system and method wherein the weight of an occupant is determined utilizing sensors located on the seat structure.
17. to provide a system and method wherein other morphological properties are used to identify an individual including facial features, iris patterns, voiceprints, fingerprints and handprints.
18. to provide new and improved vehicular seats including a weight measuring feature and weight measuring methods for implementation in connection with vehicular seats.
19. to obtain a measurement of the weight of an occupying item in a seat of a vehicle while compensating for effects caused by a seatbelt, road roughness, steering maneuvers and a vehicle suspension system.
20. to classify an occupying item in a seat based on dynamic forces measured by a weight sensor associated with the seat, with an optional compensation for effects caused by the seatbelt, road roughness, etc.
21. to determine whether an occupying item is belted based on dynamic forces measured by a weight sensor associated with the seat, with an optional compensation for effects caused by the seatbelt, road roughness, etc.
22. to determine whether an occupying item in the seat is alive or inanimate based on dynamic forces measured by a weight sensor associated with the seat, with an optional compensation for effects caused by the seatbelt, road roughness, etc.
23. to determine the location of the occupying item on a seat based on dynamic forces measured by a weight sensor associated with the seat, with an optional compensation for effects caused by the seatbelt, road roughness, etc.
Further objects of the present invention will become apparent from the following discussion of the preferred embodiments of the invention.
Accordingly, to achieve at least one of the above objects and possibly others, a vehicle in accordance with the invention comprises a seat having a seat portion and a back portion and an arrangement for obtaining information about an occupying item in the seat. The arrangement comprises a distance-determining sensor arranged in the back portion of the seat and enabling the determination of the distance between the occupying item and the back portion, an angle sensor arranged in connection with the seat for detecting an angle between the back portion and the seat portion, and a seat displacement sensor arranged in connection with the seat for detecting longitudinal displacement of the seat.
Additional sensors systems can be used to provide additional information about the occupying item, such as a weight sensing system arranged in connection with the seat for measuring weight applied to the seat by the occupying item and one or more wave-based, capacitance or electric field sensor systems arranged to provide information about the position of the occupying item.
In one embodiment, a processor is coupled to the angle sensor and the seat displacement sensor and provides an output indicative of the identity of the occupying item based in part on information provided by the angle sensor and the seat displacement sensor.
Optionally, a component adjustment system is coupled to the arrangement and adjust a component operative with respect to the occupying item based in part on the information about the occupying item obtained by the arrangement. The component may be a steering column or a pedal.
An airbag system may also be coupled to the arrangement for protecting the occupying item in the event of a crash involving the vehicle. The airbag system is controlled based in part on the information about the occupying item obtained by the arrangement.
A seat adjustment system may also be coupled to the arrangement for adjusting the seat. The seat adjustment system is controlled based in part on the information about the occupying item obtained by the arrangement.
Several different distance-determining sensors may be employed including a capacitance sensor, an electric field sensor and a combination of a wave transmitter arranged to transmit waves in a direction outward away from the back portion of the seat and a wave receiver arranged to receive waves reflected from the occupying item when situated in the seat. In the latter case, a processor may be coupled to the transmitter and receiver to determine the distance between the occupying item and the back portion based on the time between the transmission and reception of the waves. The wave transmitter may be an ultrasonic or electromagnetic wave transmitter.
The distance-determining sensor is optionally arranged in a headrest and enables the determination of the distance between the occupying item and the headrest.
The angle sensor may be arranged in connection with a coupling portion of the seat between the back portion and the seat portion.
A seat in accordance with the invention comprises a seat portion, a back portion pivotable relative to the seat portion, a distance-determining sensor arranged in the back portion and enabling the determination of the distance between an occupying item of the seat and the back portion, an angle sensor arranged in connection with the seat portion and the back portion for detecting an angle between the back portion and the seat portion and a seat displacement sensor arranged in connection with the seat portion for detecting longitudinal displacement of the seat relative to the vehicle. The same options available in the vehicle described above can be used for the seat as well. For example, the seat may be provided with a weight sensing system.
The seat can also include a processor coupled to the angle sensor and the seat displacement sensor and arranged to provide an output indicative of the identity of the occupying item based in part on information provided by the angle sensor and the seat displacement sensor.